1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Yuri [45]
3 years ago
8

A man pushes a shopping cart across a level floor. What force resists the effort force? A) gravity B) friction C) the normal for

ce D) the reaction force
Physics
1 answer:
Kipish [7]3 years ago
8 0

Answer:

B) Friction

Explanation:

Friction is a force that acts when an object is sliding along a surface. Microscopically, this force is due to the fact that the two surfaces are not perfectly smooth, but they have "imperfections" that cause a force that opposes the motion of the object.

For an object sliding on a flat surface, the force of friction has magnitude:

F_f = \mu_k mg

where

\mu_k is the coefficient of kinetic friction

m is the mass of the object

g is the acceleration of gravity

The direction of the force of friction is always opposite to the direction of motion of the object.

In reality, friction also acts if the object is at rest and it is pushed by a force; in this case, we talk about static friction, and its magnitude is

F_f = \mu_s mg

where \mu_s is called coefficient of static friction, and it is generally larger than the coefficient of kinetic friction.

You might be interested in
Calcula la fuerza magnética de una carga que se desplaza hacia la derecha con una velocidad de 5 X 10 a la 6 metros sobre segund
Diano4ka-milaya [45]

Answer:

La fuerza magnética del electrón es 6.41x10⁻¹³ N.

Explanation:

Podemos encontrar la fuerza magnética (F) usando la ley de Lorentz:

F = qv\times B

En donde:

q: es la carga del electrón = 1.602x10⁻¹⁹ C

v: es la velocidad del electrón = 5x10⁶ m/s

B: es el campo magnético = 0.8 T

F = qv\times B = 1.602 \cdot 10^{-19} C*5\cdot 10^{6} m/s*0.8 T = 6.41 \cdot 10^{-13} N                                

Por lo tanto, la fuerza magnética del electrón es 6.41x10⁻¹³ N.

Espero que te sea de utilidad!  

3 0
3 years ago
Two car collide in an intersection. The speed limit in that zone is 30 mph. The car (mass of 1250 kg) was going 17.4 m/s (38.9).
Musya8 [376]

Answer:

u₂ = 3.7 m/s

Explanation:

Here, we use the law of conservation of momentum, as follows:

m_1u_1+m_2u_2=m_1v_1+m_2v_2\\

where,

m₁ = mass of the car = 1250 kg

m₂ = mass of the truck = 2020 kg

u₁ = initial speed of the car before collision = 17.4 m/s

u₂ = initial speed of the tuck before collision = ?

v₁ = final speed of the car after collision = 6.7 m/s

v₂ = final speed of the truck after collision = 10.3 m/s

Therefore,

(1250\ kg)(17.4\ m/s)+(2020\ kg)(u_2)=(1250\ kg)(6.7\ m/s)+(2020\ kg)(10.3\ m/s)\\\\(2020\ kg)(u_2) = 8375\ N.s + 20806\ N.s - 21750\ N.s\\\\u_2=\frac{7431\ N.s}{2020\ kg}

<u>u₂ = 3.7 m/s</u>

5 0
3 years ago
Olivia is on a swing at the playground. if the swing is moving from W to Z, at which point is her kinetic energy increasing and
s2008m [1.1K]

Answer:

from W-Z.. i think on a swing you get your most potential energy at W and Z is where you go up so Z would be where the kinetic energy increased and W is where potential energy decrease

Explanation:

hope this helps

4 0
2 years ago
A speed-time graph is a horizontal line with a y-value of 4. Which describes the objects motion?
taurus [48]
It means the speed is constant with a value of 4 units.
5 0
3 years ago
A 8kg cat us running 4 m/s. How much kenetic energy is that
Flauer [41]
     Using the Definition of Kinetic Energy, we have:

E_{c}= \frac{mv^2}{2}  \\ E_{c}= \frac{8*4^2}{2}  \\ \boxed {E_{c}=64J}
3 0
3 years ago
Other questions:
  • Which is the goal of science?
    14·2 answers
  • if you put something like apiece of cardboard between a magnet and a iron nail, the magnet still holds the nail. how?
    9·1 answer
  • A Ferris wheel car is moving in a circular path at a constant speed. Is the car accelerating?
    9·1 answer
  • Doubling an object’s height will have what effect on its potential energy due to gravity?
    11·1 answer
  • How long does it take a plane that is traveling at 350 km/h to travel 1750 km?
    9·1 answer
  • Now, consider whether the following statements are true or false:_____________________________________.
    14·1 answer
  • 4.80-kg bucket of water is accelerated upward by a cord of negligible mass whose breaking strength is 75.0 N. If the bucket star
    9·2 answers
  • Turns red lithmus paper blue
    8·1 answer
  • Information is in the photo
    10·1 answer
  • If the velocity of sound is 330m/s ,what is the wavelength of the wave of 100Hz ​
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!